Summed Break and MAB time - E1.20 RDM (Remote Device Management) Protocol Forums

dangeross · July 6th, 2009

E1.20 - 2006 states in section 3.2.1 Responder Packet Timings "RDM responders shall conform to the timing specified in Table 3-3". Table 3-3 line 1 shows max Receive Break and MAB times as 1S. Later in the same section it is stated "Break timing has been modified from the DMX512 standard. The minimum has been lengthened to allow In-Line devices to decrease this time as they pass the data through".
I would interpret the above to mean that a responder must accept packets meeting the timing requirements of Table 3-3 line 1 even though the maximum time values are greater than the allowed Controller Packet maximums.
As far as measuring the break time if your micro supports edge triggered GPIO interrupts on your UART Rx pin you can enable a rising edge interrupt as soon as the UART detects a break and then measure the time to the rising edge of the DMX/RDM break.

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July 6th, 2009	#4
dangeross Junior Member Join Date: Feb 2009 Posts: 13	E1.20 - 2006 states in section 3.2.1 Responder Packet Timings "RDM responders shall conform to the timing specified in Table 3-3". Table 3-3 line 1 shows max Receive Break and MAB times as 1S. Later in the same section it is stated "Break timing has been modified from the DMX512 standard. The minimum has been lengthened to allow In-Line devices to decrease this time as they pass the data through". I would interpret the above to mean that a responder must accept packets meeting the timing requirements of Table 3-3 line 1 even though the maximum time values are greater than the allowed Controller Packet maximums. As far as measuring the break time if your micro supports edge triggered GPIO interrupts on your UART Rx pin you can enable a rising edge interrupt as soon as the UART detects a break and then measure the time to the rising edge of the DMX/RDM break.